Mosca (Spanish for fly) is an unincorporated community and a U.S. Post Office in Alamosa County, Colorado, United States.

The climate in this area is characterized by warm to hot, dry summers, and cold to freezing winters.

[5] Much of the local economy is based on tourism due to the town's proximity with Great Sand Dunes National Park.

FairPoint Communications operated the Columbine Telecom Company in the community.

[6] Mosca is served by the Sangre de Cristo School District Re-22J.